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Interpreting The Paleoenvironmental Context Of Marine Shales Deposited During The Cambrian Radiation: Global Insights From Sedimentology, Paleoecology, And Geochemistry, Tristan Kloss Dec 2012

Interpreting The Paleoenvironmental Context Of Marine Shales Deposited During The Cambrian Radiation: Global Insights From Sedimentology, Paleoecology, And Geochemistry, Tristan Kloss

Theses and Dissertations

Many Cambrian marine shales are traditionally thought to have been deposited under dysoxic or anoxic conditions based upon interpretations of sedimentological and ichnological fabrics. Recently a number of geochemical studies have suggested the opposite, that some Cambrian marine shales were deposited under slightly oxic to well-oxygenated conditions. Despite the significant implications redox conditions have for the paleoenvironment, paleoecology, and taphonomy of Cambrian shales, rarely are these disparate sedimentological and geochemical approaches combined for direct comparisons in a singular study of Cambrian shales. A multidisciplinary approach is used here, combining sedimentological, paleoecological, and geochemical approaches, for re-interpreting the paleoenvironmental conditions of …


Insights Into The Early Transgressive History Of Lake Bonneville From Stratigraphic Investigation Of Pilot Valley Playa, Ut/Nv, Usa, Kevin A. Rey Oct 2012

Insights Into The Early Transgressive History Of Lake Bonneville From Stratigraphic Investigation Of Pilot Valley Playa, Ut/Nv, Usa, Kevin A. Rey

Theses and Dissertations

Multiple shallow sediment cores were obtained from Pilot Valley playa, a sub-basin located in the northwestern Bonneville basin. Analysis of stratigraphy, ostracodes, mineralogy, chemistry, total inorganic carbon (TIC), total organic carbon (TOC), and stable isotopes were performed to better place these sediments into proper context with respect to the Lake Bonneville cycle. Results showed Pilot Valley playa contains a nearly full sequence of Lake Bonneville deep-water marl in addition to sediments deposited before and after the Lake Bonneville cycle. Within the marl is a sequence of organic rich algal laminated marl correlated with the Stansbury oscillation. Four 14C ages ranging …


The Role Of Case-Hardening In The Development And Preservation Of Narrow, Vertical-Walled Canyons In Adršpach-Teplice, Czech Republic, Shawn Austin Wiggins Oct 2012

The Role Of Case-Hardening In The Development And Preservation Of Narrow, Vertical-Walled Canyons In Adršpach-Teplice, Czech Republic, Shawn Austin Wiggins

Theses and Dissertations

The geomorphology at Adršpach-Teplice, Czech Republic is dominated by vertical-walled, fracture-controlled features including slot canyons, gorges and pillars. Surfaces of canyon walls in Adršpach are case-hardened and more resistant to erosion than the bulk of the sandstone, which appears to be fundamental to the formation and preservation of canyons. Core and whole rock samples from Adršpach-Teplice were analyzed in thin section, including SEM analysis with cathodo luminescence. XRF and XRD analyses indicated that silica case-hardened surfaces are chemically and mineralogically similar to the rock interior, while iron case-hardened surfaces have an increase in iron present at the surface as the …


Discriminant Analysis Of Xrf Data From Sandstones Of Like Facies And Appearance: A Method For Identifying A Regional Unconformity, Paleotopography,And Diagenetic Histories, Stephen Paul Phillips Sep 2012

Discriminant Analysis Of Xrf Data From Sandstones Of Like Facies And Appearance: A Method For Identifying A Regional Unconformity, Paleotopography,And Diagenetic Histories, Stephen Paul Phillips

Theses and Dissertations

The placement of an unconformable surface within a stratal succession affects the interpreted thickness of units and sequences in contact with that surface. Unit thickness influences the interpretation of basin subsidence, paleotopography, diagenesis, and depositional style. Accurate placement of an unconformity results in true formational thicknesses for formations associated with that unconformity. True thicknesses aid in producing more precise surface to subsurface correlations, isopach maps, and paleogeographic maps. An unconformity may be difficult to identify in the stratal succession due to similar rocks above and below the unconformity and the presence of multiple candidate surfaces. Using statistical discriminant analysis of …


Self-Organizing Fluid Flow Patterns In Crystalline Rock: Theoretical Approach To The Hydrothermal Systems In The Middle Fork Of The Boise River, Scott A. Himes Jul 2012

Self-Organizing Fluid Flow Patterns In Crystalline Rock: Theoretical Approach To The Hydrothermal Systems In The Middle Fork Of The Boise River, Scott A. Himes

Theses and Dissertations

The thermal springs along the Middle Fork of the Boise River (MFBR) within the Atlanta lobe of the Idaho batholith discharge in discrete locations that appear to be part of self-organizing flow systems. Infiltrating water flows through Basin and Range fractures to depth where it is heated and ultimately discharged at the intersection of trans-Challis oriented faults along the MFBR. Isotopic compositions of the thermal waters have a linear trend with elevation suggesting that the recharge locations are near each thermal spring and the hydrothermal system is not one large interconnected system, but rather multiple individual hydrothermal systems. Water chemically …


Geologic Map Of The Deer Point Quadrangle, Garfield County, Utah, Nicholaus D. Driscoll Jul 2012

Geologic Map Of The Deer Point Quadrangle, Garfield County, Utah, Nicholaus D. Driscoll

Theses and Dissertations

A new geologic map of the Deer Point 7.5' quadrangle located in the southern region of Capitol Reef National Park in south-central Utah provides stratigraphic and structural detail not previously available. The Deer Point quadrangle was mapped at a scale of 1:24,000 and is the fourth geologic map completed at this scale in Capitol Reef National Park. Twelve Quaternary units and eighteen bedrock formations and members are exposed in the Deer Point quadrangle. Bedrock formations range in age from Triassic to Cretaceous. The details not available on previous geologic maps include: four alluvial terrace units, two lacustrine units, two mass …


Mineral Chemistry Of Basalts Recovered From Hotspot Snake River Scientific Drilling Project, Idaho: Source And Crystallization Characteristics, Richard W. Bradshaw Jul 2012

Mineral Chemistry Of Basalts Recovered From Hotspot Snake River Scientific Drilling Project, Idaho: Source And Crystallization Characteristics, Richard W. Bradshaw

Theses and Dissertations

Mineral chemistry and petrography of basalts from the Kimama drill core recovered by Hotspot: Snake River Scientific Drilling Project, Idaho establish crystallization conditions of these lavas. Twenty-three basalt samples, from 20 individual lava flows were sampled from the upper 1000 m (of the 1912 m drilled) core drilled on the axis of the Snake River Plain, and represent approximately 3 m.y. of volcanism (rocks at the bottom of the hole are ~6 Ma). Rock from the upper 1000 m are typically fresh, while those lower in the core are more altered and are less likely to preserve fresh phenocrysts to …


Temporal Trends In West Antarctic Accumulation Rates: Evidence From Observed And Simulated Records, Landon Kelly Burgener Jul 2012

Temporal Trends In West Antarctic Accumulation Rates: Evidence From Observed And Simulated Records, Landon Kelly Burgener

Theses and Dissertations

Reconstructed snow accumulation rate observations from five new firn cores show a statistically significant negative trend in accumulation rates over the past four decades across the central West Antarctic ice sheet. A negative temporal trend in accumulation is unexpected in light of rising surface temperatures and simulations run by GCMs. Both the magnitude of the mean accumulation rates and the range of interannual variability observed in the new records compares favorably to older records, suggesting that the new accumulation rate records may serve as a regional proxy for recent temporal trends in West Antarctic accumulation rates. The observed negative trend …


Mafic Alkaline Magmatism In The East Tintic Mountains, West-Central Utah: Implications For A Late Oligocene Transition From Subduction To Extension, Tara Laine Allen Mar 2012

Mafic Alkaline Magmatism In The East Tintic Mountains, West-Central Utah: Implications For A Late Oligocene Transition From Subduction To Extension, Tara Laine Allen

Theses and Dissertations

Voluminous Eocene to Oligocene intermediate to silicic volcanic rocks related to subduction erupted throughout the Great Basin and were supplanted by bimodal eruptions of basalt and rhyolite related to extension in the Miocene. Locally, in the northern East Tintic Mountains of central Utah, this important transition is marked by a distinctive package of mafic alkaline magmas that reveal important details about the nature of this fundamental change. A late Oligocene anorthoclase-bearing shoshonite lava in the Boulter Peak quadrangle contains megacrysts of anorthoclase, with phenocrysts of olivine, clinopyroxene, magnesiohastingsite, magnetite, and apatite. The anorthoclase grains occur as glomerocrysts with irregular, resorbed …


Three-Dimensional Seismic Study Of Pluton Emplacement, Offshore Northwestern New Zealand, Jason Allen Luke Feb 2012

Three-Dimensional Seismic Study Of Pluton Emplacement, Offshore Northwestern New Zealand, Jason Allen Luke

Theses and Dissertations

Detailed 3D seismic images of a volcano-plutonic complex offshore northwestern New Zealand indicate the intrusive complex lies in a relay zone between NE-trending en echelon normal faults. A series of high angle normal faults fan out from the margin of the Southern Intrusive Complex and cut the folded strata along the margin. These faults terminate against the margins of the intrusion, extend as much as 1 pluton diameter away from the margin, and then merge with regional faults that are part of the Northern Taranaki Graben. Offset along these faults is on the order of 10s to over 100 meters. …


Diagenesis Of The Middle Member Of The Bakken Formation, Williston Basin, North Dakota, Katharine L. Kimber Jan 2012

Diagenesis Of The Middle Member Of The Bakken Formation, Williston Basin, North Dakota, Katharine L. Kimber

Theses and Dissertations

The shales of the Bakken Formation have been extensively studied since the discovery of oil, but little attention has been paid to the middle reservoir member. Successfully produced wells are concentrated in multiple fields throughout the Williston Basin, there has been no definitive way to determine a well’s potential productivity. This study used core samples, point counting, and petrography to determine the diagenetic traits common to the Middle Member of the Bakken Formation and their effect on oil production. Cores from forty-one wells were examined. Thin sections were made from sixteen cores, eight producing wells and eight dry wells. All …


Terrestrial Heat Flow And An Assessment Of Enhanced Geothermal System Resources In Minnesota, Robert Car Lloyd Klenner Jan 2012

Terrestrial Heat Flow And An Assessment Of Enhanced Geothermal System Resources In Minnesota, Robert Car Lloyd Klenner

Theses and Dissertations

Low heat flow has been previously reported in Minnesota (406 mW m-2) and the Superior Province of the Canadian Shield (42 ± 8 mW m-2). Low heat flow in Minnesota is due to heat flow measurements made in the mafic rocks of the Mid-Continent Rift System (MCRS) and attributed to the lack of correction for post-glacial climate fluctuations. Radioactivity is a critical heat flow component, particularly in Minnesota where all published heat flow sites are located within the MCRS, creating a bias in the data. The rift is a massive mafic intrusive complex that extends from Moho to the surface, …


Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis Jan 2012

Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis

Theses and Dissertations

The Deccan Plateau in western and central India has been a major area of interest for researchers since the 1800s. In 1840, James Sowerby described the molluscan collection sent to him by John Malcolmson. In 1860, Stephen Hislop identified new molluscan species and redescribed based on better preserved material. Although this seminal work was comprehensive, interpretations have changed since the mid 1800s. Species need to be reassigned to current and/or accurate taxa, as well as revalidated statistically. Seventeen character traits were measured on over 600 specimens from five eastern Deccan Plateau localities representing a stratigraphic and temporal sequence. Cluster analysis …


Study On Underground Coal Gasification Combined Cycle Coupled With On-Site Carbon Capture And Storage, Peng Pei Jan 2012

Study On Underground Coal Gasification Combined Cycle Coupled With On-Site Carbon Capture And Storage, Peng Pei

Theses and Dissertations

The North Dakota portion of the Williston basin holds huge, but economically unmineable lignite resources in the Fort Union formation. A technology coupling the underground coal gasification with carbon capture and storage (UCG-CCS) is proposed in this study to recover these lignite resources in North Dakota. The UCG-CCS system provides a cost-effective and environment-friendly approach to convert the lignite to electricity and beneficially utilize the by-product of CO2 at the same time. The target coal seam is the Harmon lignite in the Fort Union formation in western North Dakota. The main objectives of this study are to set up the …


A Geophysical Investigation Of The Northeastern Rim Of The St. Martin Impact Structure, Manitoba, Canada, Vladimir B. Zivkovic Jan 2012

A Geophysical Investigation Of The Northeastern Rim Of The St. Martin Impact Structure, Manitoba, Canada, Vladimir B. Zivkovic

Theses and Dissertations

The St. Martin impact structure is a 40 Km diameter structure located in Manitoba, Canada lies in featureless, glaciated terrain lacking any surface expression of an impact structure. The age of the structure has been re-determined to range between 224.3 Ma to 241.4 Ma which nullified a previous hypothesis suggesting this impact was part of a multiple impact event. Within the proposed structural boundary two outcrops of Archean granite are present. The first outcrop is located in what has been identified as the central peak of the impact structure. The second outcrop lies along the northeastern boundary and is known …